1. Technical Field
The present application relates to a method for transferring nanostructures.
2. Discussion of Related Art
It is well-known that growing nanostructures by chemical vapor deposition (CVD) highly depends on proper substrates. For example, horizontally aligned single-walled carbon nanotubes (SWCNTs) and large-area graphene of high quality can be grown on quartz substrates and copper foils by CVD, respectively. However, it is more desirable to fabricate electronic and optoelectronic devices with nanostructures on silicon wafers or flexible substrates. Thus, a transfer technology is proposed and developed to transfer the nanostructure from a growth substrate to a target substrate.
The transfer technology generally utilizes a sacrificial layer as the media. The sacrificial layer can be organic materials. The nanostructures on a growth substrate are first coated with the organic materials, an organic layer can be formed. Then the organic layer attached with the nanostructures is separated from the growth substrate and transferred to the target substrate. Finally the organic layer is removed by dissolving in acetone or by annealing in an argon atmosphere.
However, it may be difficult to completely remove residues of the organic layer from the nanostructures and the target substrate, which resulting in poor contact between the nanostructures and the post-fabricated metal electrodes. Moreover, removing the organic layer by annealing in an argon atmosphere cannot be applied to plastic substrates, because the plastic substrates cannot withstand high temperature.
What is needed, therefore, is to provide a method for transferring nanostructures that can overcome the above-described shortcomings.